Shocks due to irregularities in the road and engine vibration, both of which are transmitted to a bulb through the vehicle frame, are primary causes of bulb failure due to breakage of the relatively delicate bulb filaments. Bulb failure, particularly at the rear of the vehicle, may not be immediately apparent to the vehicle operator. The loss of the ability to signal following vehicles as to turning and braking presents a danger and often results in a violation of the law. Occassionally, even if bulb failure is known, the replacement is not immediate. Thus, it is always desirable to extend bulb life.
Various lamp assemblies have been proposed incorporating resilient insulative bulb mounts. In one assembly, the mount (which is suspended between a pair of posts) holds the bulb directly, no metallic socket is employed. This requires that the contact for each filament, as well as the metallic base of the bulb, be soldered to lead wires. Such an arrangement makes it difficult if not functionally impossible to replace a bulb, particularly if the vehicle is on the road when replacement is desired. For further information regarding the structure and operation of such a mount, reference may be made to U.S. Pat. No. 4,390,936.
U.S. Pat. No. 3,980,878 is directed to a lamp assembly including a resilient isolation mount having lateral side portions held in cavities with the cavities closed by overlying plates having apertures receiving pins. The metal socket used with the mount has portions at its bulb-receiving end which must be bent to retain the socket in the mount.
Other vehicular lamp assemblies include resilient mounts which are of relatively massive construction, have supports adjacent only one end of the mount and require the use of relatively complex socket or contact structures. Such sockets or contacts may be difficult to insert in the mounts and may not be removable without damage to the mounts. Furthermore, crimping or soldering is required for connection of the ground conductor. For further information regarding the operation and structure of such mounts and sockets, reference may be made to U.S. Pat. Nos. 3,114,508; 3,143,301 and 4,176,391.